Andrew Gomes

Electrocoagulation treatment of municipal wastewater in Torreon Mexico

Abstract One of the biggest challenges of the twenty-first century is to provide water, primarily potable, to the majority of the world population. This is a critical issue, especially in developing countries. One way to augment that effort is to reuse water. Currently, some emerging wastewater treatment technologies based on electrochemistry (e.g. electrocoagulation (EC), electroflotation, electrodecantation, and electrooxidation) are available that are competitive and advantageous over conventional technologies. Although EC has been known for more than a century, it has not been comprehensively studied. EC has been commercialized for the removal of specific contaminants and wastewater treatment. This work demonstrates EC as an alternative method for the treatment of municipal wastewater in Torreon; Coah, Mexico. COD value for wastewater in Torreon is considered as medium level (245 ppm). Experiments were conducted to determine the optimum operational conditions. Results show a remarkable removal efficie...

Thin Films and Coatings for Absorptive Removal of Antimicrobials, Antibiotics, and Other Pharmaceuticals

The US EPA regards “emerging pollutants” as new unregulated chemicals which impact the environment and human health. Many chemicals such as analgesics, anti-inflammatories, beta-blockers, antibiotics, and antimicrobials are not being effectively removed in water treatment. Triclosan, a ubiquitous antimicrobial that is widely used in antibacterial products and in clinical situations is of growing concern as it has been found to degrade human health with potentially devastating promotion of cancer and autoimmune diseases. In this study we are exploring the removal of triclosan using molecular modeling and absorptive/adsorption experiments on modified clays monitored by Tandem Liquid Chromatography — Mass Spectrometry (LCMS). Thin films and coatings offer the opportunity to build complex structures, save materials and engineer hybrid systems. Manual coating (brushing, dipping and air spraying) as well as 3D printing has been explored.

Characterization of Copper-Manganese-Aluminum-Magnesium Mixed Oxyhydroxide and Oxide Catalysts for Redox Reactions

Complex multi-metal catalysts require several stages in their preparation. These are: co-mixing, co-precipitation, milling and sol-gel, drying, dehydroxylation, and calcination and sometimes regeneration of the hydroxide by rehydration. These processes require thermal analysis (DTA, TGA, DSC) and accompanying off gas analysis, plus one or more of these: XRD, XPS, SEMEDS, FTIR and UV-VIS. In this study, hydrotalcite, hopcalite and mixed systems were prepared and guided by the above characterization techniques. The systems were initiated by mixing the chlorides or nitrates followed by hydrothermal treatments to produce the hydroxides which were further treated by washing, drying, and calcination. The thermal analysis was critical to guide the preparation through these stages and when combined with structural determination methods considerable understanding of their chemical and physical changes was obtained. The correlations between preparation and characterization will be discussed.

Technical Innovation and Entrepreneurial Potential of “Hydrotalcite Like” Materials

The process of technological innovation embraces a sequence of activities that translates technical and scientific knowledge into physical reality to be used on a scale having substantial societal impact. This goes beyond invention to accumulation of technical data, expansion of necessary knowledge, transformation into product and its diffusion and adaptation for significant impact. Hydrotalcite like materials or double layered hydroxides in general have been a playground for discovery, have shown a history of innovation, and have the potential for an even greater surge in innovation in the future that can drive an enormous expansion in technology entrepreneurship. The versatility for use in energy materials, composites, bioactives, electrochemicals, environmentals, anticorrosives, catalysts, drugs, coatings, and yet to be discovered uses are enormous. The pathways and barriers to new innovations and entrepreneurial activities are discussed in this overview in context of their science and technology.

Layered Double Hydroxides in Energy Research: Advantages and Challenges

Layered Double Hydroxides (LDH) are being used in energy related research for last several years. Among others, research interests include synthesis of catalysts, electrocatalysts, photocatalysts, electrode materials for batteries and super capacitors, and luminescence materials. They can be also applied for the production of renewable energy sources, such as hydrogen and oxygen. LDH materials have several advantages in general, such as their low cost, versatility of their chemical composition, easily manipulated properties, a wide range of preparation variables, unique anion exchange and intercalation properties, chemical stability, and colloidal and thermal behavior. On the other hand, their use in particular energy research produces some challenging physical and chemical aspects that need to be addressed. These include lack of knowledge on exact structure, postulation of interlayer arrangement, and some selectivity issues in catalysis. In this work, we will revisit these topics with an overview of the historical background and current literature survey.